Total Commander

It used to work but now I can't access the internal shared storage and external sdcard. I can access the root system but going into storage, mnt, etc and I can't go into the drives. It has full storage permissions.

From what I recall there was something mentioned about some restrictions in some update but I don't remember and I haven't used it much. The build in file explorer works.

I updated to recent and same problem. Is there any way to fix this? Maybe force permissions using adb? (I remember seeing somewhere some hacks that could be set)

The problem is caused by Google restrictions:
There are two ways to access files:
1. Direct access to the file system (file:// url)
2. Access to files shared by other apps (content:// url)
In newer Android versions, Google is restricting direct access to the file system to just a few app types, like file managers or backup tools. All others have to use a file picker, which then returns a content url shared by the Android file manager.

Therefore when you click on a file in Total Commander now, it sends it to the called program as a content url. If your book app can still access file urls, you can create an internal association in Total Commander where you disable the "content://url" option to still send file urls to that app.